K2, the relatively new marijuana-like synthetic drug is a mix of herbs and spices sprayed with a synthetic compound that is chemically similar to THC, the psychoactive ingredient in marijuana. It's produced in Korea and China and has a lot of health workers concerned as there are many reports of it being undetectable on drug tests.

State lawmakers in Missouri and Kansas have recently introduced bills to make the drug illegal as health experts warn that more teenagers are buying it, using it and at risk. (As is, in most states, anyone--even a 10 year old-- could walk into a store where it's sold and buy some.)

From MSNBC: "Though banned in most of Europe, K2's key ingredients are not regulated in the United States." Furthermore,"there is no data on the drug's toxicity or how long it stays in the body. In mice, it can lead to a lower body temperature, partial paralysis and the temporary inability to feel pain, according to the DEA."